Gas is its own unit, decoupled from ETH. Opcodes cost a certain amount of gas to execute [1]. When creating a transaction, a sender sets the maximum amount of gas that they are willing to pay. This is the "gas limit."
I know what gas is. It would be more accurate to call it a unitless number describing the relative resource cost factor of each opcode.
If you define the term gas as a unit then it refers to both a value, and the unit of that value, which is where most of the confusion comes from. The language "1000 gas" could mean either "1000 wei/szabo/whatever of gas" or "1000 gasCost" which are 2 completely different things!
If you define the term gas as a unit then it refers to both a value, and the unit of that value, which is where most of the confusion comes from. The language "1000 gas" could mean either "1000 wei/szabo/whatever of gas" or "1000 gasCost" which are 2 completely different things!